Two parallel wires carrying currents in the opposite directions____________________?

A. Repel each other
B. Attract each other
C. Have no effect upon each other
D. They cancel out their individual magnetic fields

A magnetic field___________________?

A. Always exerts a force on a charged particle
B. Never exerts a force on a charged particles
C. Exerts a force if the charged particle is moving in the direction of the magnetic field lines
D. Exerts a force if the charged particle is moving perpendicular to the magnetic field lines

Which one of the following material is most suitable for making core of an electromagnet ?

A. Air
B. Steel
C. Cu-ni alloy
D. Soft iron

The relationship between Tesla and smaller unit Gauss of magnetic induction is given by_________________?

A. 1t = 103 g
B. 1t = 10-4 g
C. 1t = 10-2 g
D. 1t = 104 g

The standard vector symbol for flux density is ____________________?

A. M
B. L
C. H
D. B

An electron enters a region where the electric field E is perpendicular to the magnetic field B. It will suffer no deflection if_________________?

A. E = bev
B. B = ee/v
C. E = bv
D. E = bev/2

n instrument which can measure potential without drawing any current is_____________________?

Aa. voltmeter
B. Galvanometer
C. Cathode ray oscilloscope (cro)
D. Ammeter

When the coil of the galvanometer is in equilibrium then the deflecting couple is____________________?

A. Zero
B. Equal to the restoring couple
C. Greater than the restoring couple
D. Smaller than the restoring couple

Which one of the following is not an electromechanical instrument ?

A. Galvanometer
B. Voltmeter
C. Ammeter
D. Ac transformer and dc generator

In a multi range ammeter as the range increases _____________________?

A. Shunt value decreases
B. Shunt value increases
C. Shunt value remains the same
D. None of the above